Dental press



Jan. 1, 1957 M. 1... LAPPlN ET AL 2,775,790

DENTAL PRESS Filed Feb. 12, 1954 INVENTORJ, 12401. L ZANDBEQG, Mu. TONI. LAP/DIN,

. y 2 7 ATTOPA/Ef United States Patent 2,775,790 DENTAL PRESS Milton L.Lappin and Paul I. Zandberg, Los Angeles, Calif.

Application February 12, 1954, Serial No. 409,870

1 Claim. (Cl. 18 -33) The present invention relates to a dental press,sometimes termed a clamp or compress. The device of the invention isadapted to be used with a vulcanizing flask.

An object of the invention is the provision of a press which allows theoperator to quickly close a flask under pressure and maintain the flaskclosed during a vulcanizing operation.

At the present time, the general procedure is to employ a flask havingtwo parts, to wit, a lower half and an upper half, which parts areseparable and provided with a groove and tongue edges for holding theparts in alignment. A model of the denture base is constructed with waxon the cast, which may likewise include the teeth, assuming that anupper or lower denture is to be formed. This denture base is invested inthe lower half of the flask, usually with the use of plaster orartificial stone. After the stone or plaster has set, a separatingmedium of some kind is applied and allowed to dry. The upper half of theflask is then placed in position and filled with artificial stone orplaster, which is allowed to harden thoroughly. Following this, the twohalves of the flask are separated, and the wax which formed the model ofthe denture base is removed. After removal of the wax, a mold results,and into this mold is placed the material which forms the denture base.Various materials are utilized in the industry, such as vulcanite, whichis a thermo-cure, or a thermo-plastic of some type, such as an acrylicresin, vinyl resin, Glyptal resins, and phenolformaldehyde resins.Whatever the material used may be, this material is placed in the moldor space formerly occupied by the wax. Usually, the surfaces of the moldare treated with some liquid to prevent the denture material fromadhering to the mold. As a rule, the material fills the lower half ofthe flask and to a height above the edge of said lower half of theflask. Thereafter, the top half of the flask is placed over the lowerhalf, followed by tightly closing the flask. The press utilized fortightly closing the flask forms the present invention. As a rule,devices now known to the inventors for clamping or compressing thevulcanizing flask are diflicult to use,'

time consuming, often require more than one person to manipulate, andare otherwise unsatisfactory.

An object of the present invention is the provision of a press for adental flask which will quickly and easily close the flask and hold theflask against opening when subjected to internal pressure.

A further object is the provision of a dental press which is easilymanipulated by an operator, either to open or close the press.

A further object is the provision of a press which is economical in costof manufacture, and generally superior to presses now known to theinventors.

With the above mentioned and other objects in view, the inventionconsists in the novel and useful provision, formation, construction,association, and relative arrangement of parts, members and features,all as shown in a certain embodiment in the accompanying drawing, de-

Patented Jan. 1, 1957 scribed generally, and more particularly pointedout in the claim.

In the drawing:

Figure 1 is a side elevation of the dental press, holding a flask, priorto applying pressure to the flask,

Figure 2 is a fragmentary sectional view on the line 2--2 of Figure 1,

Figure 3 is a view taken on the line 3-3 of Figure 2, one of the membersof the invention being moved so as to initially apply pressure to theflask, and,

Figure 4 is a fragmentary sectional view on an enlarged scale, showingthe flask when the parts thereof have been pressed together.

Referring now with particularity to the drawing, the improved pressincludes a base member 1, two spacedapart, parallel side members orwalls 2 and 3 secured to the base member and in substantially rightangular relationship to the base member, and which base member hasportions extending beyond the side members, as shown in Figure 2, at 4and 5. A top member 6 overlies the side members 2 and 3. As shown in thefigures, the top is substantially square in outline, and is providedwith through bores adjacent corners thereof. One of said bores is shownat 7, and is counter-bored at 8. Passed through the bore 7 andcounterbore 8 is a screw 9 for reception in a threaded bore 10 in eachside wall 2 and 3. Surrounding the screw and received in the counterbore8 and resting on the top of each side member is a coil spring 11, whichat all times tends to expand and lift the cover member 6 above the upperedges of the side members 2 and 3. Quite obviously, relative spacingbetween the tops of the side members 2 and 3 and the said cover isobtained by adjusting the screws 9 within the threaded bores 10. Thecover member is formed centrally thereof with an elongated slot 12.Adapted to be carried by the member 6 is a head 13 constituting a memberhaving two right angularly related parts 14 and 15. Part 13 is providedwith an end socket adapted to receive one end of an operating lever 16,while the part 14 is provided with thrust portions 17 and 18. The throatportion 17 is formed by curving the end wall of part 15, while thrustportion 18 comprises a small curved protuberance on the side of portion15. The head 13 is passed through the slot 12 and pivotally secured tothe member 6 by one or more pintle pins which extend transverselythrough a transverse bore in the member 6, as shown in Figure 2, at 19.More particularly, a bail 20 is provided which permits the press to behandled and carried, the pintle pins forming that portion of the bailwhich is passed through the bore 19 and a transverse bore 21 in thehead.

To stabilize the device in use, we have provided a foundation or basemember 22, provided with a pair of parallel, angular flanges 23 and 24,between which are received the portions 4 and 5 of the base. As shown inFigure 2, the angular character of the flanges prevent any tippingmovement of the base 1.

The operation, uses and advantages of the press just described are asfollows:

In the showing of the drawing, we have provided a two-part flask havingan upper half 25 and a lower half 26. When a flask of this character isplaced upon the base 1 of the press, the upper half 25 will be raisedabove the upper edge of the lower half 26, due to the presence of anexcess of denture base material therein. The open ator having adjustedthe screws 9 for the given flask and the degree of movement necessary toclose the two halves of the flask together, applies over the upper halfof the flask a pressure plate 27, whereupon the lever 16 is swung fromthe position shown in Figure l to the position shown in Figure 3, whichwill bring the thrust element 18 into engagement with pressure plate 27.Thrust element 18 will move the pressure plate slightly downwardly tomove the upper half 25 toward the lower half 26 of the flask. Uponswinging the lever downwardly to the position shown in Figure 4, thethrust element 17 is brought into full engagement centrally of thepressure plate and of the flask to close both halves tightly together.The operator then removes the lever 16 from the socket end of portion 1or" the head 13, and the press, together with the flask containing thedenture to be treated, may then be placed in a boiling pan, in the usualmanner.

After a given length of time, as determined by the operator, the presstogether with the flask, are removed from the boiling pan and theoperator may again insert the portions 4 and 5 of the press between theflanges 23 and 24, reinsert the lever 16 in the socket of portion id anda slight upward movement will move the thrust element 17 over thepressure plate, bringing the thrust element 18 into position, thesprings iii moving the top member 6 upwardly from the side members 2 and3, whereupon further tilting of the lever to, say, the position ofFigure 1, will allow the flask to be removed from the press, thepressure plate removed from the top of the flask, and the flask coverand base separated in the usual manner.

It will be noted upon reference to Figures 1 and 3 that the thrustelements 17 and 18 move from one side of dead center relative to thepivot point for the head with the top member 6, to dead center. Thus,the lever may be maintained in any one of several positions, and theoperator is assured that the flask will be closed tightly and underconsiderable pressure when the head is in the position shown in Figure4. It is evident that considerable pressure must be exerted between thetwo flask portions to force them together when the denture material iswithin the mold, and this excess of material will flow from between theupper and lower halves of the flask.

We claim:

A press for dental flasks, including a base upon which a dental flask isadapted to be supported, a pair of parallel side members extending fromone surface of said base to a position above the top of the flask, a topmember spanning the side members secured to the base, headed screwspassed through said top member for reception in threaded bores extendinginwardly from the tops of the side members, coil springs surroundingsaid headed screws for urging the top member to engage the heads of saidscrews to separate the top member from the tops of the side walls, theheaded screws adjustably and positively spacing the top member from thetops of the side members; said top member provided with a transverseslot, a head having first and second leg portions in right angularrelationship, said first leg portion extending through the slot of saidtop member, means pivoting said first leg portion to the top member,said first leg portion having a curved end forming one thrust elementand the side of said first leg portion provided with a second thrustelement, and means secured to the other leg of said head for swingingthe said head to bring one or the other of said thrust elements intoengagement with the top of the flask.

References Cited in the file of this patent UNITED STATES PATENTS861,598 Moscovitz July 30, 1907 1,172,564 Rutan Feb. 22, 1916 1,539,828Campbell June 2, 1925 2,501,527 Levinsohn et a1. Mar. 21, 1950 2,620,512Larson Dec. 9, 1952

